Background

Dr. Erturk began at Georgia Tech in May 2011 as an Assistant Professor. Prior, he worked as a Research Scientist in the Center for Intelligent Material Systems and Structures at Virginia Tech. His postdoctoral research interests included theory and experiments of piezoelastic structures for applications ranging from aeroelastic energy harvesting to nonlinear vibrations of electroelastic systems.

His Ph.D. dissertation was centered on experimentally validated electromechanical modeling of piezoelectric energy harvesters using analytical and approximate analytical techniques. Prior to his Ph.D. studies in Engineering Mechanics at Virginia Tech, Dr. Erturk received his M.S. degree from the Middle East Technical University (METU, Ankara, Turkey) and his M.S. thesis was related to analytical and semi-analytical modeling of spindle – tool holder – tool dynamics in machining centers for predicting chatter stability and identifying interface dynamics between the assembly components.

Research

Dr. Erturk’s theoretical and experimental research interests are at the intersection of dynamical systems and smart structures with applications to novel multiphysics problems.

Energy harvesting from dynamical systems is one of Dr. Erturk’s primary research topics. The goal in this research field is to enable self-powered electronic components by harvesting ambient energy. Potential applications of low-power harvesting range from energy-autonomous medical implants to wireless sensor networks in structural health monitoring. Dr. Erturk’s research in this field spans from electromechanical modeling and experimental investigations for design and optimization of vibration-based energy harvesters to performance enhancement by exploiting nonlinear dynamic phenomena, such as interwell chaos and large-orbit limit-cycle oscillations. To this end, monostable and bistable nonlinear electromechanical oscillators are established, modeled, and tested in his lab (figure a). Nonlinear energy harvesters offer enhanced frequency bandwidth and potentially outperform their linear counterparts under harmonic excitation at different frequencies. Linear and nonlinear stochastic electroelastic problems are also explored for scavenging mechanical energy from non-deterministic environments (figure b), such as civil infrastructure systems undergoing human and vehicle loads.

One of Dr. Erturk’s research collaborations (intersecting with the discipline of Aerospace Engineering) combines the domains of piezoelectricity and aeroelasticity to establish unconventional and scalable ways of airflow energy harvesting through electroaeroelasticity (figure c). Such scalable devices can be used in powering sensor nodes located in high wind areas. Nonlinearities in this multiphysics problem are of interest due to their inherent presence as well as to reduce the cut-in speed of persistent electrical response under flow excitation.

Bio-inspired aquatic and aerial structures with smart materials are also investigated as scalable and effective research platforms to explore other multiphsyics problems, such as aquatic locomotion and flapping-wing aircraft (figure d). A novel untethered piezoelectric robotic fish was developed and tested in Dr. Erturk’s lab and proven to outperform its alternative smart material-based swimmer counterparts. Potential applications of geometrically scalable and energy-efficient aquatic robotics by piezohydroelastic actuation range from sustainability in marine environments to effective drug delivery in medicine.

Near future directions of Dr. Erturk’s research include low-power sustainability in civil infrastructure systems, energy-efficient morphing and biomimetic flapping of aeroelastic structures, morphing using multistable composites, energy-efficient multi-directional thrust generation in hydroelastic structures, multifunctional underwater locomotion and energy harvesting systems, energy harvesting from structure-borne or air-borne propagating waves, exploiting nonlinear dynamics to enable broadband MEMS designs and nonlinear vibration absorbers, stochastic dynamics of electroelastic structures, investigation of other transduction methods and non-piezoelectric materials for vibration-based energy harvesting. One of Dr. Erturk’s present research collaborations (intersecting with Atomistic Modeling and Materials Science) is focused on the gradient effects in centrosymmetric dielectrics for potential applications to energy harvesting, sensing, and actuation at very small scales.

Dr. Erturk’s research topics involve active collaborations with colleagues from the disciplines of Mechanical Engineering, Aerospace Engineering, Electrical Engineering, Civil Engineering, and Materials Science. He has worked on projects funded by the Air Force Office of Scientific Research, the Office of Naval Research, the National Institute of Standards and Technology, and the National Science Foundation.

The interdisciplinary research topics mentioned here utilize both theoretical and experimental techniques. Therefore the students involved will be able to develop theoretical modeling skills along with an appreciation of experimental aspects. Conducting research in these topics will provide the students with a bridge between the concepts of structural dynamics and smart materials as well as theoretical and experimental modal analysis with applications to novel multiphysics problems. The students will have the opportunities to interact and collaborate with other research groups, develop strong technical communication and presentation skills, and regularly participate in technical conferences.